Method, apparatus, and computer program for detecting one or more objects in the sea floor

A non-transitory, computer-readable medium having a program code for performing a method of detecting one or more objects in a sea floor when the program code is executed on a computer, a processor, a control module, or a programmable hardware component, the method causing the computer, the processor, the control module, or the programmable hardware component to:

• activate an at least one acoustic signal source to transmit a plurality of acoustic signals into the sea floor, wherein a wavelength of the plurality of acoustic signals is selected to be of the same order of magnitude as an expected size of the one or more objects;
• obtain, from a plurality of acoustic receivers, a receiver signal comprising electrical waveforms generated in response to acoustic pressure waves scattered by the plurality of acoustic signals at the one or more objects in the sea floor;
• generate a detection grid, the detection grid representing a grid at the points of which the one or more objects are being localized, the detection grid extending both below an area spanned by the plurality of acoustic receivers and offset from the area;
• group portions of the receiver signal to points of the detection grid;
• perform a travel-time correction of the portions of the receiver signal with respect to the points of the detection grid to align the electrical waveforms generated by the scattering into a coherent seismic event;
• combine the travel-time-corrected portions of the receiver signal at the points of the detection grid;
• and
• detect the one or more objects at the points of the detection grid both below the area spanned by the plurality of acoustic receivers and offset from the area based on the combination of the travel-time-corrected portions of the receiver signal, wherein the detection of the one or more objects is based on the scattering of the plurality of acoustic signals at the one or more objects.

An apparatus for detecting one or more objects in a sea floor, the apparatus comprising:

• an interface coupled to at least one acoustic signal source and a plurality of acoustic receivers, and
• a processing module configured to:
• activate the at least one acoustic signal source to transmit a plurality of acoustic signals into the sea floor, wherein a wavelength of the plurality of acoustic signals is selected to be of the same order of magnitude as an expected size of the one or more objects;
• obtain, from the plurality of acoustic receivers, a receiver signal comprising electrical waveforms generated in response to acoustic pressure waves scattered by the plurality of acoustic signals at the one or more objects in the sea floor;
• generate a detection grid, the detection grid representing a grid at the points of which the one or more objects are being localized, the detection grid extending both below an area spanned by the plurality of receivers and offset from the area;
• group portions of the receiver signal to points of a detection grid,
• perform a travel time correction of the portions of the receiver signal with respect to the points of the detection grid to align the electrical waveforms generated by the scattering into a coherent seismic event,
• combine the travel time corrected portions of the receiver signal at the points of the detection grid, and
• detect the one or more objects at the points of the detection grid both below the area spanned by the plurality of receivers and offset from the area based on the combination of the travel time corrected portions of the receiver signal, wherein the detection of the one or more objects is based on the scattering of the multiple acoustic signals at the one or more objects.